The present invention relates to guiding magnetic tape past a tape access head.
Magnetic tape is commonly used to store voice and data information due to its reliability, cost efficiency, and ease of use. One way in which magnetic tape may be made more useful and cost effective by increasing the density of information stored on the magnetic tape. One method of increasing information density is to decrease the thickness of the tape thereby permitting more tape to be stored in a given volume. Another way of improving magnetic tape storage is to increase the rate of information transfer. This may be accomplished by increasing the speed at which the tape passes the tape access head.
Decreasing the thickness of magnetic tape creates difficulties in a tape transport system. Thin tape stretches, increasing the possibility of read and write errors. Tape stretching is exacerbated by complex tape transport systems which require more tension on the tape. Thin tape also may require mechanical support within the tape transport system to prevent folding, kinking, creasing, curling and other mechanical damage. Further, thin tape is more easily skewed relative to the tape head.
Various tape transport techniques have been proposed. Some of these solutions use a belt or carrier ribbon to support the tape along some portion of the tape path. Previous belt techniques, however, typically fail to provide one or more features necessary for thin, rapidly moving tape. A first feature is to provide support for the magnetic tape to prevent damage. A second feature is to guide the magnetic tape into proper position and alignment with the tape head. A third feature is to dissipate air that may be trapped when the tape contacts the belt.
What is needed is an effective tape transport system for thin tape. The tape transport system must be able to move magnetic tape past the tape head without stretching or mechanical damage. The tape should also be properly aligned with the tape head. The tape transport system should further be simple, inexpensive, and easy to maintain.
It is an object of the present invention to guide thin magnetic tape past a tape head.
It is another object of the present invention to position magnetic tape relative to the tape head.
It is still another object of the present invention to protect magnetic tape along the tape path.
It is yet another object of the present invention to reduce the complexity of the tape path.
In carrying out the above objects and other objects and features of the present invention, a tape transport system for positioning magnetic tape moving over a tape head is provided. The tape system includes a carrier ribbon having a width equal to the tape width. Passages through the carrier ribbon permit air, such as might otherwise trapped between the magnetic tape and the carrier ribbon, to pass through the carrier ribbon. At least one carrier ribbon guide is positioned on either side of the tape head. Each carrier ribbon guide has a channel of substantially the same width as the carrier ribbon for positioning the magnetic tape and the carrier ribbon across the tape head. A ribbon drive moves the carrier ribbon past the ribbon guides.
In an embodiment of the present invention, the carrier ribbon is formed in a continuous loop.
In an another embodiment of the present invention, the carrier ribbon drives the tape at the tape speed past the tape head.
In still another embodiment of the present invention, the tape transport system includes at least one lift-off pin operative to move the magnetic tape and the carrier ribbon away from the tape head such as, for example, during high speed rewind.
In yet another embodiment of the present invention, the tape transport system includes at least one air jet nozzle for moving the magnetic tape and the carrier ribbon away from the tape head.
A method of transporting magnetic tape past the tape head is also provided. The method includes driving a carrier ribbon in the tape direction. The tape contacts a carrier ribbon in a region of the tape path prior to the tape head. Any air that would otherwise be trapped between the magnetic tape and the carrier ribbon passes through the carrier ribbon. The magnetic tape is guided past the tape head. The tape separates from the carrier ribbon in a region of the tape path after the tape head.
The above objects and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings.